The Commodore 16 was a budget home computer from the mid 1980s, the entry-level model in a wider range of machines. As its name suggests it only has 16k of memory in keeping with its budget status, and while it has the rest of the hardware necessary to run software intended for its 64k stablemates, that 16k is impossible to expand without modifying the machine. Should you have a ’16 in your collection this is not a particularly arduous process, and Tynemouth Software have gone into great detail over how it can be achieved.
As was quite common in machines of the period, the address lines for the RAM area above the fitted 16k are not wired to disable it when those addresses are selected, so the same 16k appears mirrored three times in the space between it and the 64k limit. Thus simply plugging in a 64k cartridge would result in the top 48k being unusable, and some means of disabling or supplanting the internal chips was called for. Contemporary upgrades required pin or track snipping, but as they go on to show us there are some less ugly alternatives both permanent and reversible. Whichever you might favor they all at least don’t carry the huge cost hurdle in 2019 that they might have been when the machine was new. Sadly even though their cases may be similar the resulting machine will not be a Commodore 64, not even a new one.
Long-time Hackaday readers will know that the hardware designer for these machines was our Hackaday colleague [Bil Herd], and all followers of Commodore and his work should read his account of the CES trade show at the heady height of Commodore’s fame.